How to force YUM/DNF to use IPv4

Introduction

IPv6 addresses are preferred over IPv4 addresses for DNS resolution. If the hostname in a repository's URL has an AAAA record, your server will ignore the A record and attempt to contact the hostname at the IPv6 address, even if the IPv4 address is accessible and the IPv6 address isn't. YUM and DNF can be configured to only use IPv4 addresses for DNS resolution.

Procedure

1. Access the server's command line as the 'root' user via SSH or "Terminal" in WHM.
2. Open the YUM/DNF configuration file in your preferred text editor.
   • Open /etc/yum.conf if your server uses YUM.
   • Open /etc/dnf/dnf.conf if your server uses DNF.
3. Add the following line.

   ip_resolve=4

4. Save the changes and close the text editor.